The prior art and medical practitioners have long recognized the desirability to deliver drugs or other bioactive or pharmacologically active agents directly to a specific location in the body instead of by systemic delivery. Localized delivery is particularly desirable in vascular applications, for example, to deliver drugs adapted to prevent restenosis as may occur after a procedure such as angioplasty or stent placement. For example, one such technique is described in U.S. Pat. No. 5,102,402 (Dror) in which a coating of body-affecting chemicals in the form of microcapsules are applied to the exterior of a balloon of a balloon catheter. The coating releases from the balloon when the balloon is inflated into contact with and against the vascular lumen to be treated.